Dibenzofurane polymers for electroluminiscent devices

ABSTRACT

Disclosed are electroluminescent materials comprising a homopolymer based on recurring structural units of the formula (I) wherein R 9 , R 9′  R 9″ , R 11 , R 13  R 14 , R 11′ , R 13′ , R 14′  independently are H or an organic substituent, where at least one of R 9 , R 9′  R 9″ , R 11 , R 13  R 14 , R 11′ , R 13′ , R 14′  comprises a group R 10  of the formula —(Sp) x10 -[PG′]&lt; wherein Sp is a divalent organic spacer, PG′ is a group derived from a polymerizable group, and x10 is 0 or 1, with substituents and spacer as defined in claim  1 . Further disclosed are some novel polymers of this class as well as monomers for their preparation. The homopolymers are advantageously used as a host material in devices further comprising a luminescent component, which is usually selected from phosphorescent metal complexes and fluorescent dopants.

The present invention pertains to some novel electroluminiscentmaterials, some novel materials (especially polymers) for theirpreparation, a process for the preparation of the novelelectroluminiscent materials, as well as electroluminiscent devicescontaining the novel electroluminiscent materials or polymers, andcorresponding uses.

Some dibenzofurane homopolymers have been mentioned in GB-601568, U.S.Pat. No. 3,294,763, FR-1441442 and GB-1077085, inter alia asphotoconducting materials. WO 08/029652 discloses some oligomers andpolymers inter alia combining carbazole and dibenzofurane units.

It has now been found that certain side chain dibenzofurane polymers mayreplace commonly used polyvinylcarbazole (PVK) as a host material inOLEDs, especially for Iridium based triplett emitters (TEs), and givehigh quantum yield and efficiency.

The invention therefore pertains to an electroluminescent materialcomprising a homopolymer based on recurring structural units of theformula I

whereinR⁹, R^(9′) R^(9″), R¹¹, R¹³, R¹⁴, R^(11′), R^(13′), R¹⁴′ independentlyare H or an organic substituent, where at least one of R⁹, R^(9′)R^(9″), R¹¹, R¹³, R¹⁴, R^(11′), R^(13′), R¹⁴′ comprises a group R¹⁰ ofthe formula—(Sp)_(x10)-[PG′]<wherein Sp is a divalent organic spacer, PG′ is a group derived from apolymerisable group, and x10 is 0 or 1.

Any organic substituent in formula I, if present, is usually selectedfrom halogen; OH; C₁-C₂₄alkoxy; C₂-C₂₄alkoxy which is substituted by Eand/or interrupted by D; C₁-C₂₄alkyl; C₁-C₂₄alkyl which is substitutedby E and/or interrupted by D; C₁-C₂₄haloalkyl; C₂-C₂₄alkenyl;C₂-C₂₄alkynyl; C₁-C₂₄alkylthio; C₁-C₂₄acyl; C₅-C₂₄aryl; C₆-C₂₄aryl whichis substituted by G; C₁-C₂₀heteroaryl; C₂-C₂₀heteroaryl which issubstituted by G; C₇-C₂₅aralkyl; C₃-C₁₂cycloalkyl; C₁-C₂₄acyloxy;C₅-C₁₀aryloxy; C₃-C₁₂cycloalkyloxy; COR; CH═NR; CH═N—OH; CH═N—OR; COOR;OCOR; CONHR; NHCOR; CONRR′; CONH—NHR; CONH—NRR′; SR; SO₂R; SO₃R; SO₂NHR;SO₂NRR′; SO₂NH—NHR; SO₂NH—NRR′; S(O)R; S(O)OR; S(O)NHR; S(O)NRR′;S(O)NH—NHR; S(O)NH—NRR′; SiRR′R″; GeRR′R″; PRR′; PORR′; PO(OR)R′;PO(OR)₂; PO(NHR)₂; PO(NRR′)₂; CN; NO₂; NHR; NRR′; NH—NHR; NH—NRR′,CONROH;

where R, R′ and R″ independently are selected from C₁-C₁₂alkyl,C₁-C₁₂haloalkyl, C₅-C₁₀aryl, C₃-C₁₂cycloalkyl; and R may also behydrogen;

or two substituents R⁹, R¹¹, R¹³, R¹⁴, R^(9′), R^(11′), R^(13′) andR^(14′), which are adjacent to each other, together form a group

R¹⁰⁵, R¹⁰⁶, R¹⁰⁷, R¹⁰⁸, R^(105′), R^(106′), R^(107′) and R^(108′) areindependently of each other H, C₁-C₁₈alkyl, C₁-C₁₈alkyl which issubstituted by E and/or interrupted by D, C₁-C₁₈alkoxy, or C₁-C₁₈alkoxywhich is substituted by E and/or interrupted by D;D is —CO—; —COO—; —S—; —SO—; —SO₂—; —O—; —NR²⁵—; —SiR³⁰R³¹—; —POR³²—;—CR²³═CR²⁴—; or —C≡C—;andE is —OR²⁹; —SR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; —CN; orhalogen;G is E, C₁-C₁₈alkyl, C₃-C₁₂cycloalkyl, C₂-C₁₈alkyl which is interruptedby D, C₁-C₁₈perfluoroalkyl, or C₁-C₁₈alkoxy which is substituted by Eand/or interrupted by D, wherein R²³, R²⁴, R²⁵ and R²⁶ are independentlyof each other H; C₆-C₁₈aryl; C₆-C₁₈arylalkyl; C₃-C₁₂cycloalkyl;C₆-C₁₈aryl or C₆-C₁₈arylalkyl which is substituted by C₁-C₁₈alkyl and/orC₁-C₁₈alkoxy; C₁-C₁₈alkyl; or C₂-C₁₈alkyl which is interrupted by —O—;orR²⁵ and R²⁶ together form a five or six membered ring;R²⁷ and R²⁸ are independently of each other H; C₆-C₁₈aryl;C₆-C₁₈arylalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkyl which is substituted byC₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl; C₃-C₁₂cycloalkyl; orC₂-C₁₈alkyl which is interrupted by —O—;R²⁹ is H; C₆-C₁₈aryl; C₆-C₁₈arylalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkylwhich is substituted by C₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl;C₂-C₁₈alkylcarbonyl; C₃-C₁₂cycloalkyl; or C₂-C₁₈alkyl orC₂-C₁₈alkylcarbonyl which is interrupted by —O—;R³⁰ and R³¹ are independently of each other C₁-C₁₈alkyl,C₃-C₁₂cycloalkyl, C₆-C₁₈aryl, or C₆-C₁₈aryl, which is substituted byC₁-C₁₈alkyl, andR³² is C₁-C₁₈alkyl, C₆-C₁₈aryl, or C₆-C₁₈aryl, which is substituted byC₁-C₁₈alkyl, R, R′ and R″ independently are selected from C₁-C₁₂alkyl,C₁-C₁₂haloalkyl, C₅-C₁₀aryl, C₅-C₁₀aryl, C₃-C₁₂cycloalkyl, preferablyfrom C₁-C₆alkyl, phenyl, cyclopentyl, cyclohexyl; andAr independently is selected from C₅-C₁₀aryl, or C₅-C₁₀aryl which issubstituted by C₁-C₁₈ alkyl;and one of R⁹, R^(9′) R^(9″), R¹¹, R¹³, R¹⁴, R^(11′), R^(13′), R¹⁴′,R¹⁰⁵, R¹⁰⁶, R¹⁰⁷, R¹⁰⁸, R^(105′), R^(106′), R^(107′), R^(108′) is agroup R¹⁰ of the formula—(Sp)_(x10)-[PG′]<wherein Sp is a divalent organic spacer, PG′ is a group derived from apolymerisable group, and x10 is 0 or 1.

The spacer unit Sp, which may be present in the group R¹⁰, typically isof the formula(X₃-D)_(x11)-X₂,wherein x11 is 0 or 1; X₃, X₂ independently are O, C₁-C₄alkylene-O,CH₂—CHOH—CH₂—O, S, C₁-C₄alkylene-S, NR22, C₁-C₄alkylene-NR22, COO,C₁-C₄alkylene-COO or C₁-C₄alkylene-OCO, CONR22, C₁-C₄alkylene-CONR22 orC₁-C₄alkylene-NR22CO, NR22CONR22, C₁-C₄alkylene-NR22CONR22,C₁-C₄alkylene, CH₂CHOHCH₂, or a direct bond, andD is C₁-C₂₄alkylene, interrupted C₃-C₂₄alkylene, C₂-C₂₄alkenylene,C₂-C₂₄alkynylene, C₆-C₁₀arylene. Preferred spacer units Sp are X₂ (i.e.those of the above wherein x11 is 0), where X₂ is a direct bond, O,C₁-C₄alkylene-O, CH₂—CHOH—CH₂—O, COO, CONR22, C₁-C₄alkylene, orCH₂CHOHCH₂.

PG′ is a group derived from a polymerisable group, it is trivalent sinceit is anchored on Sp (or its anchor position in formula I) and it isintegrated in the polymer chain, or crosslinked polymer network, of thepresent invention. A typical group of moieties PG′ thus are derived fromethylenically unsaturated monomers or strained oxygen ring systems,including those of the formulae

where the asterisk (*) indicates its bonding position to Sp or themoieties of formula I and R is as defined above, while the 2 furtheropen bonds provide integration into the polymer chain. These moietiesare especially suitable for introducing the desired functionalities asside chains into the final polymer of the invention, or as crosslinkingmoieties. Corresponding polymerizable groups PG include vinyl, allyl,1-methylvinyl (isopropenyl), (meth)acryloyl, vinylphenyl (styryl),oxiranyl, glycidyl, oxetanyl etc. Other moieries PG′ are those derivedfrom from moieties PG described further above, e.g. those introducingthe desired functionalities into the main chain of the polymer of theinvention.

The homopolymers used in the electroluminescent materials of theinvention may be isotactic or syndiotactic or, usually, atactic.

The electroluminescent material further comprises a luminiscentcomponent usually selected from phosphorescent metal complexes andfluorescent dopants as known in the art.

The present polymers show especially good results with regard tosolution processing or printing (e.g. in case of non-crosslinkedpolymers), long-term stability of the electroluminescent device (e.g.resistance against migration/segregation/crystallization as well asagainst oxidation/heat) as well as its brightness and efficiency.

The term “ligand” is intended to mean a molecule, ion, or atom that isattached to the coordination sphere of a metallic ion. A “monodentateligand” contains only 1 coordination site, while a “bidentate ligand”contains 2 coordination sites, both of which are attached to themetallic centre. The term “complex”, when used as a noun, is intended tomean a compound having at least one metallic ion and at least oneligand. The term “group” or “moiety” is intended to mean a part of acompound, such as a substituent in an organic compound or a ligand in acomplex. The term “substituted” is intended to mean replacement of ahydrogen atom in an organic group or compound by a (typically organic)substituent.

The term “organic substituent” stands for an organic (i.e. C, Hcontaining) or (hetero)functional radical (e.g. consisting ofheteroatoms and optionally either of C or H); usually, any organicsubstituent, if present, makes up a minor part of the compound; examplesfor organic substituents are organic radicals containing 1 to 20 carbonatoms and optionally further (e.g. 1-10) heteroatoms, heterofunctionalradicals typically comprising 1 to 5 heteroatoms.

Heteroatoms in organic or heterofunctional radicals are usually selectedfrom O, S, N, P, Si, B, as well as halogen (i.e. any of F, Cl, Br, I; inthe electroluminescent material of the invention especially fluoro)making up such a radical.

Organic substituents, if present, often are selected from halogen, OH,C₁-C₂₄alkoxy, C₁-C₂₄alkyl, C₁-C₂₄haloalkyl, C₂-C₂₄alkenyl,C₂-C₂₄alkynyl, C₁-C₂₄alkylthio, C₁-C₂₄acyl, C₅-C₁₀aryl,C₁-C₁₀heteroaryl, C₃-C₁₂cycloalkyl, C₁-C₂₄acyloxy, C₅-C₁₀aryloxy,C₃-C₁₂cycloalkyloxy, or from the residues COR (i.e. aldehyde or ketogroup), CH═NR, CH═N—OH, CH═N—OR, COOR, OCOR, CONHR, NHCOR, CONRR′,CONH—NHR, CONH—NRR′, SR, SO₂R, SO₃R, SO₂NHR, SO₂NRR′, SO₂NH—NHR,SO₂NH—NRR′, S(O)R, S(O)OR, S(O)NHR, S(O)NRR′, S(O)NH—NHR, S(O)NH—NRR′, asilyl or germanyl group (SiRR′R″, GeRR′R″), PORR′, PO(OR)R′, PO(OR)₂,PO(NHR)₂, PO(NRR′)₂, cyano (CN), NO₂, NHR, NRR′, NH—NHR, NH—NRR′,CONROH;

where R, R′ and R″ independently are selected from C₁-C₁₂alkyl,C₁-C₁₂haloalkyl, C₅-C₁₀aryl, C₃-C₁₂cycloalkyl, preferably fromC₁-C₆alkyl, phenyl, cyclopentyl, cyclohexyl;

and R may also be hydrogen. Common substituents are often selected fromC₁-C₁₂alkyl, a hydroxyl group, a mercapto group, C₁-C₁₂alkoxy,C₁-C₁₂alkylthio, halogen, halo-C₁-C₁₂alkyl, a cyano group, an aldehydegroup, a ketone group, a carboxyl group, an ester group, a carbamoylgroup, an amino group, a nitro group or a silyl group.

Any condensed ring or ring system formed by two neighbouring residuessuch as Q¹ and Q² or two residues R⁴¹ (see below) as an organic bridginggroup, together with their anchor atoms form a carbocyclic orheterocyclic, non-aromatic or preferably aromatic ring, typically of 5to 7 ring atoms in total, often is selected from aryl, heteroaryl,cycloalkyl, or cycloaliphatic unsaturated moieties as explained below.

The term “haloalkyl” means groups given by partially or whollysubstituting the above-mentioned alkyl group with halogen, the termincludes C₁-C₂₄perfluoroalkyl, which is branched or unbranched, such asfor example —CF₃ (trifluoromethyl), —CF₂CF₃, —CF₂CF₂CF₃, —CF(CF₃)₂,—(CF₂)₃CF₃, and —C(CF₃)₃.

The “aldehyde group, ketone group, ester group, carbamoyl group andamino group” include those substituted by an C₁-C₂₄alkyl group, aC₄-C₁₈cycloalkyl group, an C₆-C₃₀aryl group, an C₇-C₂₄aralkyl group or aheterocyclic group, wherein the alkyl group, the cycloalkyl group, thearyl group, the aralkyl group and the heterocyclic group may beunsubstituted or substituted. The term “silyl group” more specificallymeans a group of formula —SiR¹⁰⁵R¹⁰⁶R¹⁰⁷, wherein R¹⁰⁵, R¹⁰⁶ and R¹⁰⁷are independently of each other a C₁-C₈alkyl group, in particular aC₁-C₄ alkyl group, a C₆-C₂₄aryl group or a C₇-C₁₂aralkylgroup, such as atrimethylsilyl group.

If a substituent occurs more than one time in a group, it can bedifferent in each occurrence.

Alkyl stands for any acyclic saturated monovalent hydrocarbyl group;alkenyl denotes such a group but containing at least one carbon-carbondouble bond (such as in allyl); similarly, alkynyl denotes such a groupbut containing at least one carbon-carbon triple bond (such as inpropargyl). In case that an alkenyl or alkynyl group contains more thanone double bond, these bonds usually are not cumulated, but may bearranged in an alternating order, such as in —[CH═CH—]_(n) or—[CH═C(CH₃)—]_(n), where n may be, for example, from the range 2-50.Where not defined otherwise, preferred alkyl contains 1-22 carbon atoms;preferred alkenyl and alkynyl each contains 2-22 carbon atoms,especially 3-22 carbon atoms.

The term alkyl, whereever used, thus mainly embraces especiallyuninterrupted and, where appropriate, substituted C₁-C₂₂alkyl such asmethyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl,tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl, 1-methylpentyl,1,3-dimethylbutyl, n-hexyl, 1-methylhexyl, n-heptyl, isoheptyl,1,1,3,3-tetramethylbutyl, 1-methylheptyl, 3-methylheptyl, n-octyl,2-ethylhexyl, 1,1,3-trimethylhexyl, 1,1,3,3-tetramethylpentyl, nonyl,decyl, undecyl, 1-methylundecyl, dodecyl, 1,1,3,3,5,5-hexamethylhexyl,tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl.Alkoxy is alkyl-O—; alkylthio is alkyl-S—.

The term alkenyl, whereever used, thus mainly embraces especiallyuninterrupted and, where appropriate, substituted C₂-C₂₂alkenyl such asvinyl, allyl, etc.

Alkynyl, including C₂₋₂₄alkynyl, is straight-chain or branched,preferred is C₂₋₈alkynyl. For example, ethynyl, 1-propyn-3-yl,1-butyn-4-yl, 1-pentyn-5-yl, 2-methyl-3-butyn-2-yl, 1,4-pentadiyn-3-yl,1,3-pentadiyn-5-yl, 1-hexyn-6-yl, cis-3-methyl-2-penten-4-yn-1-yl,trans-3-methyl-2-penten-4-yn-1-yl, 1,3-hexadiyn-5-yl, 1-octyn-8-yl,1-nonyn-9-yl, 1-decyn-10-yl, or 1-tetracosyn-24-yl.

Where indicated as interrupted, any alkyl or alkylene moiety of morethan one, especially more than 2 carbon atoms, or such alkyl or alkylenemoieties which are part of another moiety, may be interrupted by anon-aromatic cyclic or aromatic cyclic (arylene or heteroarylene) moietyas defined below and/or preferably by a heterofunction such as O, S, CO,COO, OCNR22, OCOO, OCONR22, NR22CNR22, or NR22, where R22 is H,C₁-C₁₂alkyl, C₃-C₁₂cycloalkyl, phenyl. They can be interrupted by one ormore of these spacer groups, one group in each case being inserted, ingeneral, into one carbon-carbon bond, with hetero-hetero bonds, forexample O—O, S—S, NH—NH, etc., not occurring; if the interrupted alkylis additionally substituted, the substituents are generally not a to theheteroatom. If two or more interrupting groups of the type —O—, —NR22-,—S— occur in one radical, they often are identical.

Acyl stands for a residue of an organic carboxylic acid, from which itmay be formally derived by abstraction of the acid OH; examples areformyl, acetyl, propionyl, benzoyl. Generally, C₁-C₁₈ acyl stands for aradical X′—R₂₁, wherein X′ is CO or SO₂ and R₂₁ is selected frommonovalent aliphatic or aromatic organic residues, usually frommolecular weight up to 300; for example, R₂₁ may be selected fromC₁-C₁₈alkyl, C₂-C₁₈alkenyl, C₅-C₁₉aryl which may be unsubstituted orsubstituted by C₁-C₈alkyl or halogen or C₁-C₈alkoxy, C₆-C₁₅arylalkylwhich may be unsubstituted or substituted in the aromatic part byC₁-C₈alkyl or halogen or C₁-C₈alkoxy, C₄-C₁₂cycloalkyl, and in case thatX′ is CO, R₂₁ may also be H. Acyl is preferably an aliphatic or aromaticresidue of an organic acid —CO—R₂₁, usually of 1 to 30 carbon atoms,wherein R₂₁ embraces aryl, alkyl, alkenyl, alkynyl, cycloalkyl, each ofwhich may be substituted or unsubstituted and/or interrupted asdescribed elsewhere inter alia for alkyl residues, or R′ may be H (i.e.COR′ being formyl). Preferences consequently are as described for aryl,alkyl etc.; more preferred acyl residues are substituted orunsubstituted benzoyl, substituted or unsubstituted C₁-C₁₇alkanoyl oralkenoyl such as acetyl or propionyl or butanoyl or pentanoyl orhexanoyl, substituted or unsubstituted C₅-C₁₂cycloalkylcarbonyl such ascyclohexylcarbonyl.

Aralkyl is, within the definitions given, usually selected fromC₇-C₂₄aralkyl radicals, preferably C₇-C₁₅aralkyl radicals, which may besubstituted, such as, for example, benzyl, 2-benzyl-2-propyl,β-phenethyl, α-methylbenzyl, α,α-dimethylbenzyl, ω-phenyl-butyl,ω-phenyl-octyl, ω-phenyl-dodecyl; or phenyl-C₁-C₄alkyl substituted onthe phenyl ring by one to three C₁-C₄alkyl groups, such as, for example,2-methylbenzyl, 3-methylbenzyl, 4-methylbenzyl, 2,4-dimethylbenzyl,2,6-dimethylbenzyl or 4-tert-butylbenzyl. or3-methyl-5-(1′,1′,3′,3′-tetramethyl-butyl)-benzyl.

Non-aromatic cyclic (i.e. cycloaliphatic) moieties include cycloalkyl,aliphatic heterocyclic moieties, as well as unsaturated variants thereofsuch as cycloalkenyl. Cycloalkyl such as C₃-C₁₈cycloalkyl, is preferablyC₃-C₁₂cycloalkyl or said cycloalkyl substituted by one to threeC₁-C₄alkyl groups, and includes cyclopropyl, cyclobutyl, cyclopentyl,methylcyclopentyl, dimethylcyclopentyl, cyclohexyl, methylcyclohexyl,dimethylcyclohexyl, trimethylcyclohexyl, tert-butylcyclohexyl,cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cyclododecyl,1-adamantyl, or 2-adamantyl. Cyclohexyl, 1-adamantyl and cyclopentyl aremost preferred. C₃-C₁₂cycloalkyl includes cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl,cyclodecyl, cycloundecyl, cyclododecyl; preferred among these residuesare C₃-C₆cycloalkyl as well as cyclododecyl, especially cyclohexyl.Further ring structures occuring are heterocyclic aliphatic ringsusually containing 5 to 7 ring members, among them at least 1,especially 1-3, heteromoieties, usually selected from O, S, NR22, whereR22 is as explained above for interrupting NR22-groups; examples includeC₄-C₁₈cycloalkyl, which is interrupted by S, O, or NR22, such aspiperidyl, tetrahydrofuranyl, piperazinyl and morpholinyl. Unsaturatedvariants may be derived from these structures by abstraction of ahydrogen atom on 2 adjacent ring members with formation of a double bondbetween them.; an example for such a moiety is cyclohexenyl.

Wherever “aryl” is used (e.g. in C₅-C₁₀aryl, C₁-C₁₄-heteroaryl), itdenotes an aromatic ring or polycyclic ring system containing thehighest possible number of double bonds, such as preferably phenyl,naphthyl, anthrachinyl, anthracenyl, phenanthrenyl or fluorenyl. Theterm aryl mainly embraces hydrocarbon aromatic rings, examples mainlyare C₆-C₁₈aryl including phenyl, naphthyl, anthrachinyl, anthracenyl,phenanthrenyl, fluorenyl. Heteroaromatic rings such as C₁-C₁₈heteroarylmoieties contain, as part of the ring structure, one or more heteroatomsmainly selected from O, N and S; heteroaryl such as C₄-C₁₈heteroarylstands for an aryl group containing at least one heteroatom, especiallyselected from N, O, S, among the atoms forming the aromatic ring;examples include pyridyl, pyrimidyl, pyridazyl, pyrazyl, thienyl,benzothienyl, pyrryl, furyl, benzofuryl, indyl, carbazolyl,benzotriazolyl, thiazolyl, chinolyl, isochinolyl, triazinyl,tetrahydronaphthyl, thienyl, pyrazolyl, imidazolyl. Preferred areC₆-C₁₀aryl or C₄-C₁₈heteroaryl, e.g. selected from phenyl, naphthyl,pyridyl, tetrahydronaphthyl, furyl, thienyl, pyrryl, chinolyl,isochinolyl, anthrachinyl, anthracenyl, phenanthrenyl, pyrenyl,benzothiazolyl, benzoisothiazolyl, benzothienyl, especially C₆-C₁₀aryl;most preferred is phenyl, naphthyl. Any “arylene” stands for thecorresponding divalent “aryl”.

Examples are monomers containing one or more polymerizable groups (PG)such as ethylenically unsaturated moieties or strained ring systems. PGoften is a polymerisable group selected from —C(R⁴⁴)═CH₂,—NHC(O)—C(R⁴⁵)═CH₂, —OCH₂CH₂OC(O)—C(R⁴⁵)═CH₂, —OC(O)—C(R⁴⁵)═CH₂,—C(O)—C(R⁴⁶)═CH₂, —C≡C—, —C≡CR⁴⁶, —N≡C, —O—CH(CH₂CH₂CH═CH₂)₂;C₅-C₈cycloalkenyl, bicycloalkenyl (a substituted or unsubstitutedbicycloalkenyl group having 5 to 30 carbon atoms),

(1,2-epoxyether),

(oxetanyl),

whereins is an integer from 1 to 6, m1 is an integer from 1 to 6,R⁶ is hydrogen, or C₁-C₂₀alkyl,R⁴⁴ is hydrogen, or C₁-C₄alkyl, or halogen,R⁴⁵ is hydrogen, C₁-C₄alkyl, or halogen, andR⁴⁶ is hydrogen, C₁-C₄alkyl, or C₆-C₁₂aryl, orPG′ is a group derived from a polymerisable group

whereinAHG is an aromatic, or heteroaromatic residue, which can optionally besubstituted, such as

wherein each dotted line marks the bonding position of PG′,R²¹¹ and R²¹² are independently of each other halogen, —C≡CH, boronicacid, or boronic esters, —Mg-Hal, —Zn-Hal, —Sn (R²¹³)₃, wherein Hal ishalogen, and R²¹³is C₁-C₁₈alkyl, R²¹⁴ and R^(214′) are independently ofeach other H, C₁-C₁₈alkyl, C₁-C₁₈alkyl which is interrupted by D,C₁-C₁₈perfluoroalkyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which is interrupted byD, or C₇-C₂₅aralkyl. Examples for preferred groups PG are vinyl, allyl,(meth)acryloyl, styryl, oxetanyl, oxiranyl, glycidyl.

If PG is a polymerisable group

the following processes can be used for the production of polymers:

Polymerization processes involving only dihalo-functional reactants maybe carried out using nickel coupling reactions. One such couplingreaction was described by Colon et al. in J. Pol. Sci., Part A, PolymerChemistry Edition 28 (1990) 367, and by Colon et al. in J. Org. Chem. 51(1986) 2627. The reaction is typically conducted in a polar aproticsolvent (e.g., dimethylacetamide) with a catalytic amount of nickelsalt, a substantial amount of triphenylphosphine and a large excess ofzinc dust. A variant of this process is described by Ioyda et al. inBull. Chem. Soc. Jpn, 63 (1990) 80 wherein an organo-soluble iodide wasused as an accelerator.

Another nickel-coupling reaction was disclosed by Yamamoto in Progressin Polymer Science 17 (1992) 1153 wherein a mixture of dihaloaromaticcompounds was treated with an excess amount of nickel(1,5-cyclooctadiene) complex in an inert solvent. All nickel-couplingreactions when applied to reactant mixtures of two or more aromaticdihalides yield essentially random polymers. Such polymerizationreactions may be terminated by the addition of small amounts of water tothe polymerization reaction mixture, which will replace the terminalhalogen groups with hydrogen groups. Alternatively, a monofunctionalaryl halide may be used as a chain-terminator in such reactions, whichwill result in the formation of a terminal aryl group.

In general, polymerization methods and workup procedures known in thepertinent art may be applied in analogy for the present polymers,including those known as Heck, Sonogashira, Kumada reactions; reactionsmay be carried out e.g. in analogy to WO07/090773 (see passage from page21, line 12, to page 26, line 17) or WO06/097419 (see passage from page41 line 12 to page 44 line 10, and page 45, lines 15 to 34); thepassages from the latter 2 documents mentioned are hereby incorporatedby reference.

In general, the dibenzofurane moieties of the present polymers areattached as a side chain to the polymer's main chain. This architecturebrings about some advantages, e.g. in the synthesis of the compoundssince it opens the possibility to attach the desired functionality viagrafting reactions, and simplifies certain in situ formations of thedesired polymers, e.g. by coating the substrate with a suitable monomermixture, with or without addition of a photoinitiator, and polymerizingthe mixture by exposure to radiation (e.g. UV, electron beam etc.)and/or temperature.

The present polymers may be linear or crosslinked. In the case ofcrosslinked polymers, a certain fraction of the monomers making up thepresent polymer are crosslinkers (crosslinking agents), usuallycontaining 2 or more polymerizable groups.

The invention thus includes a polymer which is obtainable byhomopolymerization of a compound of the formula II

whereinone of R⁹, R^(9′), R¹¹, R^(11′), R¹³, R¹⁴, R^(13′) and R^(14′) isR^(10′), which is a group —(Sp)_(x10)-[PG], PG is a polymerisable group,especially selected from vinyl, allyl, 1-methylvinyl, (meth)acryloyl,vinylphenyl, oxiranyl, glycidyl, oxetanyl, dimethylmaleimidyl;x10 is 0 or 1;R⁹, R^(9′) are further selected from H, C₁-C₁₈alkyl, C₁-C₁₈alkyl whichis substituted by E and/or interrupted by D, C₁-C₁₈perfluoroalkyl,C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G, C₂-C₂₀heteroaryl,C₂-C₂₀heteroaryl which is substituted by G, C₂-C₁₈alkenyl,C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which is substituted by Eand/or interrupted by D, C₇-C₂₅aralkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂,—CO—R²⁸;R¹¹ and R^(11′) are further selected from hydrogen, halogen,C₁-C₁₈alkyl, C₁-C₁₈alkyl which is substituted by E and/or interrupted byD, C₁-C₁₈perfluoroalkyl, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy,C₁-C₁₈alkoxy which is substituted by E and/or interrupted by D, CN,—CO—R²⁸, SiRR′R″, GeRR′R″, POAr₂, PAr₂;R¹³, R¹⁴, R^(13′) and R^(14′) are further selected from H, halogen,C₁-C₁₈alkyl, C₁-C₁₈alkyl which is substituted by E and/or interrupted byD, C₁-C₁₈perfluoroalkyl, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted byG, C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G,C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E and/or interrupted by D, C₇-C₂₅aralkyl, CN, —CO—R²⁸,and R¹³, R¹⁴, R^(13′) and R^(14′) may also be SiRR′R″, GeRR′R″, POAr₂,PAr₂; or two substituents R⁹, R¹¹, R¹³, R¹⁴, R^(9′), R^(11′), R^(13′)and R^(14′), which are adjacent to each other, together form a group

and all other symbols are as defined above.

Preferred polymers of the present invention have a glass transitiontemperature above 100° C.

Another aspect of this invention is related to polymer blends containing1 to 99 percent of at least one polymer of the invention. The remainder1 to 99 percent of the blend is composed of one or more polymericmaterials selected from among chain growth polymers such as polystyrene,polybutadiene, poly(methyl methacrylate), and poly(ethylene oxide);step-growth polymers such as phenoxy resins, polycarbonates, polyamides,polyesters, polyurethanes, and polyimides; and crosslinked polymers suchas crosslinked epoxy resins, crosslinked phenolic resins, crosslinkedacrylate resins, and crosslinked urethane resins. Examples of thesepolymers may be found in Preparative Methods of Polymer Chemistry, W. R.Sorenson and T. W. Campbell, Second Edition, Interscience Publishers(1968). Also may be used in the blends are conjugated polymers such aspoly(phenylene vinylene), substituted poly(phenylene vinylene)s,substituted polyphenylenes and polythiophenes. Examples of theseconjugated polymers are given by Greenham and Friend in Solid StatePhysics, Vol. 49, pp. 1-149 (1995).

The electroluminescent material comprising a homopolymer as definedabove further contains a luminiscent component, which is usuallyselected from phosphorescent metal complexes (“triplett emitters”) andfluorescent dopants. It often contains one or more additionalcomponent(s), especially selected from electron transporters, holetransporters, inert polymers, viscosity modifiers, initiators, organicsalts, and stabilizers such as antioxidants and UV absorbers.

Thus, the invention further pertains to electroluminescent materialscontaining at least one further component, especially selected fromtriplett emitters (TE), electron transporters, hole transporters, inertpolymers (such as aromatic homo- or copolymers like polystyrene orfurther polymers listed above, e.g. as viscosity modifiers), initiators,organic salts (especially if soluble in the matrix, e.g. organicammonium salts). The electroluminescent materials of the invention thusoften contain 1 to 99 percent of at least one polymer of the invention,and 99 to 1 percent of one or more of the additional (auxiliary)components listed above, which often will make up the remainder of thematerial.

Monomers for the preparation of linear polymers usually contain only 1class of polymerizable group and only 1 PG (i.e. one group R¹⁰) permonomer unit, or for grafting one or more further class(es) of PGs. Forcrosslinking and/or in situ preparation of the polymer, monomerscontaining 2 or more groups PG (i.e. 2 or more groups R¹⁰) of the sametype may be used.

The polymers of this invention preferably have a weight averagemolecular weight of 2,000 Daltons or greater, especially 2,000 to1,000,000 Daltons, more preferably 10,000 to 1,000,000 and mostpreferably 20,000 to 500,000 Daltons. Molecular weights are determinedaccording to gel permeation chromatography using polystyrene standardsand/or light scattering detectors.

The polymers of the invention may be prepared following techniques knownin the art, e.g. for preparing linear or crosslinked polymers bycondensation and/or addition polymerization methods. In many cases, abasic polymer network is formed by addition polymerization of suitablemonomers containing ethylenically unsaturated moieties as PGs, e.g. byradical copolymerization using chemical radical starters,photoinitiators, actinic radiation and/or heat for the generation ofradicals and initiation of the reaction. (Co)polymers formed in a firstpreparation step may be further modified e.g. by grafting one or morefurther monomers and/or functional groups on the polymer skeleton.Reaction conditions and methods may follow, for example, those describedin WO06/097419 or WO07/090773. As mentioned above, the present polymersmay also be formed in situ on the substrate, especially in the presenceof crosslinkable monomers as described above. For example, the in situpolymerization may effectively be carried out using monomers containingan ethylenically unsaturated group PG, with a certain fraction or all(e.g. 1-100%) monomers carrying 2 or 3 groups PG of this type, andirradiating the monomers with actinic radiation (such as UV or electronbeam; in case of UV radiation occasionally in presence of aphotoinitiator).

Preferred polymers of the formula I present in the materials of theinvention are those wherein

R⁹, R^(9′) are selected from H, C₁-C₁₈alkyl, C₃-C₁₂cycloalkyl, halogen,R¹⁰, C₁-C₁₈alkyl which is substituted by E and/or interrupted by D,C₁-C₁₈perfluoroalkyl, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G,C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G,C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E and/or interrupted by D, C₇-C₂₅aralkyl, SiRR′R″,GeRR′R″, POAr₂, PAr₂, or is —CO—R²⁸;R¹¹ and R^(11′) are selected from hydrogen, halogen, especiallyfluorine, C₁-C₁₈alkyl, C₁-C₁₈alkyl which is substituted by E and/orinterrupted by D, C₁-C₁₈perfluoroalkyl, C₂-C₁₈alkenyl, R¹⁰,C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which is substituted by Eand/or interrupted by D, CN, or —CO—R²⁸, SiRR′R″, GeRR′R″, POAr₂, PAr₂;R¹³, R¹⁴, R^(13′) and R^(14′) are selected from H, halogen, especiallyfluorine, C₁-C₁₈alkyl, R¹⁰, C₁-C₁₈alkyl which is substituted by E and/orinterrupted by D, C₁-C₁₈perfluoroalkyl, C₆-C₂₄aryl, C₆-C₂₄aryl which issubstituted by G, C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which issubstituted by G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy,C₁-C₁₈alkoxy which is substituted by E and/or interrupted by D,C₇-C₂₅aralkyl, CN or —CO—R²⁸, and R¹³, R¹⁴, R^(13′) and R^(14′) may alsobe SiRR′R″, GeRR′R″, POAr₂, PAr₂;or two substituents R⁹, R¹¹, R¹³, R¹⁴, R^(9′), R^(11′), R^(13′) andR^(14′), which are adjacent to each other, together form a group

R¹⁰⁵, R¹⁰⁶, R¹⁰⁷, R¹⁰⁸, R^(105′), R^(106′), R^(107′) and R^(108′) areindependently of each other H, C₁-C₁₈alkyl, C₁-C₁₈alkyl which issubstituted by E and/or interrupted by D, C₁-C₁₈alkoxy, or C₁-C₁₈alkoxywhich is substituted by E and/or interrupted by D, or R¹⁰,D is —CO—; —COO—; —S—; —SO—; —SO₂—; —O—; —NR²⁵—; —SiR³⁰R³¹—; —POR³²—;—CR²³═CR²⁴—; or —C≡C—;andE is —OR²⁹; —SR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; —CN; orhalogen;G is E, C₁-C₁₈alkyl, C₃-C₁₂cycloalkyl, C₂-C₁₈alkyl which is interruptedby D, C₁-C₁₈perfluoroalkyl, or C₁-C₁₈alkoxy which is substituted by Eand/or interrupted by D, wherein R²³, R²⁴, R²⁵ and R²⁶ are independentlyof each other H; C₆-C₁₈aryl; C₆-C₁₈arylalkyl; C₃-C₁₂cycloalkyl;C₆-C₁₈aryl or C₆-C₁₈arylalkyl which is substituted by C₁-C₁₈alkyl and/orC₁-C₁₈alkoxy; C₁-C₁₈alkyl; or C₂-C₁₈alkyl which is interrupted by —O—;orR²⁵ and R²⁶ together form a five or six membered ring, in particular

R²⁷ and R²⁸ are independently of each other H; C₆-C₁₈aryl;C₆-C₁₈arylalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkyl which is substituted byC₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl; C₃-C₁₂cycloalkyl; orC₂-C₁₈alkyl which is interrupted by —O—;R²⁹ is H; C₆-C₁₈aryl; C₆-C₁₈arylalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkylwhich is substituted by C₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl;C₂-C₁₈alkylcarbonyl; C₃-C₁₂cycloalkyl; or C₂-C₁₈alkyl orC₂-C₁₈alkylcarbonyl which is interrupted by —O—;R³⁰ and R³¹ are independently of each other C₁-C₁₈alkyl,C₃-C₁₂cycloalkyl, C₆-C₁₈aryl, or C₆-C₁₈aryl, which is substituted byC₁-C₁₈alkyl, andR³² is C₁-C₁₈alkyl, C₆-C₁₈aryl, or C₆-C₁₈aryl, which is substituted byC₁-C₁₈alkyl, R, R′ and R″ independently are selected from C₁-C₁₂alkyl,C₁-C₁₂haloalkyl, C₅-C₁₀aryl, C₃-C₁₂cycloalkyl, preferably fromC₁-C₆alkyl, phenyl, cyclopentyl, cyclohexyl; andAr independently is selected from C₅-C₁₀aryl, or C₅-C₁₀aryl which issubstituted by C₁-C₁₈alkyl;

where formula I contains one group R¹⁰, and

R¹⁰ group —(Sp)_(x10)-[PG′]<, wherein Sp is a divalent organic spacer,PG′ is a group derived from a polymerisable group, and x10 is 0 or 1.

For example, the electroluminescent material of the invention maycomprise a polymer of the formula III

whereinn ranges from 2 to 10000;L is CH₂, CO or a direct bond;R⁹, R¹¹, R¹³, R¹⁴, are selected from H, C₁-C₁₈alkyl, halogen,C₁-C₁₈alkyl which is substituted by E and/or interrupted by D,C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G, C₂-C₂₀heteroaryl,C₂-C₂₀heteroaryl which is substituted by G, C₂-C₁₈alkenyl,C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which is substituted by Eand/or interrupted by D, C₇-C₂₅aralkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂,or is —CO—R²⁸;each of the residues R^(9″) is independently selected from those definedfor R⁹,Rx is H or methyl and all other symbols are as defined above;preferred materials of this class comprise a polymer of the formula III,wherein n ranges from 5 to 5000, especially 10 to 1000;x10 is 0;R⁹, R^(9″), R¹¹, R¹³, R¹⁴, are selected from H, C₁-C₈alkyl, fluoro,C₁-C₈alkyl which is substituted by E, C₂-C₁₈alkyl which is interruptedby D, phenyl, phenyl which is substituted by G, C₄-C₁₈heteroaryl,C₄-C₁₈heteroaryl which is substituted by G, C₂-C₈alkenyl, C₂-C₈alkynyl,C₁-C₈alkoxy, C₁-C₈alkoxy which is substituted by E, C₂-C₁₈alkoxy whichis interrupted by D, C₇-C₂₅phenylalkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂,or is —CO—R²⁸;D is —CO—; —COO—; —S—; —SO—; —SO₂—; —O—; —NR²⁵—; —SiR³⁰R³¹—; —POR³²—;andE is —OR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; —CN; or halogen;G is E, C₁-C₈alkyl, cyclohexyl, C₂-C₁₈alkyl which is interrupted by D,C₁-C₈perfluoroalkyl, C₁-C₁₈alkoxy which is substituted by E,C₂-C₁₈alkoxy which is interrupted by D, wherein R²⁵ and R²⁶ areindependently of each other H; phenyl; C₇-C₁₂phenylalkyl; cyclohexyl;phenyl or C₇-C₁₂phenylalkyl which is substituted by C₁-C₈alkyl orC₁-C₈alkoxy; C₁-C₁₈alkyl; or C₂-C₁₈alkyl which is interrupted by —O—; orR²⁵ and R²⁶ together form a five or six membered ring selected from

R²⁷ and R²⁸ are independently of each other H; phenyl;C₇-C₁₂phenylalkyl; phenyl or C₇-C₁₂phenylalkyl which is substituted byC₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl; cyclohexyl; or C₂-C₁₈alkylwhich is interrupted by —O—;R²⁹ is H; phenyl; C₇-C₁₂phenylalkyl; phenyl or C₇-C₁₂phenylalkyl whichis substituted by C₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl;C₂-C₈alkylcarbonyl; cyclohexyl; or C₂-C₁₈alkyl or C₂-C₁₈alkylcarbonylwhich is interrupted by —O—;R³⁰ and R³¹ are independently of each other C₁-C₈alkyl, phenyl, orphenyl which is substituted by C₁-C₈alkyl, andR³² is C₁-C₈alkyl, phenyl, or phenyl which is substituted by C₁-C₈alkyl,R, R′ and R″ independently are selected from C₁-C₆alkyl, phenyl,cyclopentyl, cyclohexyl; andAr is phenyl or phenyl substituted by C₁-C₈alkyl.

Asterisks in formula III indicate the progression of the polymer chain,with common end groups usually selected from hydrogen, alkyl (e.g.C₁-C₈), aryl (e.g. phenyl) or arylalkyl (e.g. benzyl) as defined aboveand/or chain termination agents, or “unreacted”, single bonded monomerunits IV:

where Rx is H or methyl and Ry is the bond to the polymer chain, or Ryis H or methyl and Rx is the bond to the polymer chain, and all othersymbols are as defined above.

Generally preferred electroluminescent material according to theinvention comprise a polymer containing 10 to 1000 structural units ofthe formula I or III, wherein x10 is 0;

any of R⁹, R^(9′) R^(9″), R¹¹, R¹³, R¹⁴, R^(11′), R^(13′), R^(14′)independently is selected from H, C₁-C₈alkyl, fluoro, C₁-C₈alkyl whichis substituted by E, C₂-C₁₈alkyl which is interrupted by D, phenyl,phenyl which is substituted by G, C₄-C₁₈heteroaryl, C₄-C₁₈heteroarylwhich is substituted by G, C₂-C₈alkenyl, C₂-C₈alkynyl, C₁-C₈alkoxy,C₁-C₈alkoxy which is substituted by E, C₂-C₁₈alkoxy which is interruptedby D, C₇-C₂₅phenylalkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂, or is —CO—R²⁸;D is —CO—; —COO—; —O—; —NR²⁵—; —SiR³⁰R³¹—; andE is —OR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; or fluoro;G is E or C₁-C₈alkyl;R²⁵ and R²⁶ are independently of each other H; C₁-C₈alkyl; cyclohexyl;R²⁷ and R²⁸ are independently of each other H; phenyl; benzyl; phenyl orbenzyl which is substituted by C₁-C₈alkyl and/or C₁-C₈alkoxy;C₁-C₈alkyl;R²⁹ is H; phenyl; benzyl; phenyl or benzyl which is substituted byC₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl; acetyl; cyclohexyl; orC₂-C₁₂alkyl which is interrupted by —O—;R³⁰and R³¹ are independently of each other methyl or phenyl, andR, R′ and R″ independently are selected from methyl, ethyl, phenyl; andAr is phenyl;especially where any of R⁹, R^(9′) R^(9″), R¹¹, R¹³, R¹⁴, R^(11′),R^(13′), R¹⁴′ independently is selected from H, C₁-C₈alkyl, SiRR′R″.

The present invention forther pertains to novel polymers, i.e. ahomopolymer of the formula III′

whereinn ranges from 5 to 10000;at least one of the residues R⁹, R^(9″), R¹¹, R¹³, R¹⁴ is selected fromC₁-C₁₈alkyl, halogen, C₁-C₁₈alkyl which is substituted by E and/orinterrupted by D, C₆-C₂₄aryl, C₆-C₂₄aryl which is substituted by G,C₂-C₂₀heteroaryl, C₂-C₂₀heteroaryl which is substituted by G,C₂-C₁₈alkenyl, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which issubstituted by E and/or interrupted by D, C₇-C₂₅aralkyl, SiRR′R″,GeRR′R″, POAr₂, PAr₂, CO—R²⁸;especially from halogen, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, SiRR′R″, GeRR′R″,POAr₂, PAr₂; while the remaining residues may also be hydrogen;D is —CO—; —COO—; —S—; —SO—; —SO₂—; —O—; —NR²⁵—; —SiR³⁰R³¹—; —POR³²—;andE is —OR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; —CN; or halogen;G is E, C₁-C₈alkyl, cyclohexyl, C₂-C₁₈alkyl which is interrupted by D,C₁-C₈perfluoroalkyl, C₁-C₁₈alkoxy which is substituted by E,C₂-C₁₈alkoxy which is interrupted by D, wherein R²⁵ and R²⁶ areindependently of each other H; phenyl; C₇-C₁₂phenylalkyl; cyclohexyl;phenyl or C₇-C₁₂phenylalkyl which is substituted by C₁-C₈alkyl orC₁-C₈alkoxy; C₁-C₁₈alkyl; or C₂-C₁₈alkyl which is interrupted by —O—; orR²⁵ and R²⁶ together form a five or six membered ring selected from

R²⁷ and R²⁸ are independently of each other H; phenyl;C₇-C₁₂phenylalkyl; phenyl or C₇-C₁₂phenylalkyl which is substituted byC₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl; cyclohexyl; or C₂-C₁₈alkylwhich is interrupted by —O—;R²⁹ is H; phenyl; C₇-C₁₂phenylalkyl; phenyl or C₇-C₁₂phenylalkyl whichis substituted by C₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl;C₂-C₈alkylcarbonyl; cyclohexyl; or C₂-C₁₈alkyl or C₂-C₁₈alkylcarbonylwhich is interrupted by —O—;R³⁰ and R³¹ are independently of each other C₁-C₈alkyl, phenyl, orphenyl which is substituted by C₁-C₈alkyl, andR³² is C₁-C₈alkyl, phenyl, or phenyl which is substituted by C₁-C₈alkyl,R, R′ and R″ independently are selected from C₁-C₆alkyl, phenyl,cyclopentyl, cyclohexyl; andAr is phenyl or phenyl substituted by C₁-C₈alkyl;L is CH₂, CO or a direct bond; Rx is H or methyl;x10 is 0 or 1 and Sp is O, C₁-C₄alkylene-O, CH₂—CHOH—CH₂—O, COO, CONR22,C₁-C₄alkylene, or CH₂CHOHCH₂.

Preferred variants and substitution patterns of the novel polymers, aswell as the method for preparation, are mainly as described furtherabove for the polymers used in the electroluminescent material of theinvention.

Some valuable monomers for the preparation of the present polymers arenovel compounds, which are of the formula V

whereinat least one of the residues R⁹, R^(9″), R¹¹, R¹³, R¹⁴ is selected fromhalogen such as iodo, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, SiRR′R″, GeRR′R″,POAr₂, PAr₂; while the remaining residues may also be hydrogen;R, R′ and R″ independently are selected from C₁-C₆alkyl, phenyl,cyclopentyl, cyclohexyl; and Ar is phenyl or phenyl substituted byC₁-C₈alkyl;L is CH₂, CO or a direct bond; Rx is H or methyl;x10 is 0 or 1 and Sp is O, C₁-C₄alkylene-O, CH₂—CHOH—CH₂—O, COO, CONR22,C₁-C₄alkylene, or CH₂CHOHCH₂.

Each of the residues R^(9″), as present e.g. in formulae III, III′, IVand V, is selected independently from the meanings indicated, theresidues thus may be identical or differ from each other.

The preparation of the monomers for the present polymeric compounds mayfollow methods known in the art, e.g. as described in the literatureinitially cited. The introduction of the polymerizable group may becompleted before a further derivatization of the monomer by introductionof any further substituent R⁹, R^(9″), R¹¹, R¹³, R¹⁴; in many cases,however, a compound containing a substituent R⁹, R^(9″), R¹¹, R¹³, R¹⁴is provided first, and this product is then converted in a second stepinto the monomer containing the polymerizable group PG. Substituents mayalso be modified in subsequent steps, e.g. after first introduction of areactive substituent such as halogen, haloalkyl, hydroxy orhydroxyalkyl.

Reaction conditions are adapted according to methods known in the art,including, but not limited to, use of solvents, temperatures, catalysts,protective measures, workup, isolation and purification procedures.Further details are explained in the present examples.

The present invention is also directed to an electronic devicecomprising the present polymer and its fabrication process. Theelectronic device can comprise at least one organic active materialpositioned between two electrical contact layers, wherein at least oneof the layers of the device includes the light emitting dopant compound,which may be a phosphorescent dopant (usually a metal complex such as anIr based triplett emitter, or a fluorescent compound). The electronicdevice can comprise an anode layer (a), a cathode layer (e), and anactive layer (c). Adjacent to the anode layer (a) is an optionalhole-injecting/transport (electron blocking) layer (b), and adjacent tothe cathode layer (e) is an optional electron-injection/transport (holeblocking) layer (d). Layers (b) and (d) are examples of charge transportlayers.

The active layer (c) preferably comprises at least approximately 0.1weight percent of the luminiscent dopant (often more than 1%, or 0.1 to10%).

The device may include a support or substrate adjacent to the anodelayer (a) or the cathode layer (e). Most frequently, the support isadjacent the anode layer (a). The support can be flexible or rigid,organic or inorganic. Generally, glass or flexible organic films areused as a support. The anode layer (a) is an electrode that is moreefficient for injecting holes compared to the cathode layer (e). Theanode can include materials containing a metal, mixed metal, alloy,metal oxide or mixed-metal oxide. Suitable metal elements within theanode layer (a) can include the Groups 4, 5, 6, and 8-11 transitionmetals. If the anode layer (a) is to be light transmitting, mixed-metaloxides of Groups 12, 13 and 14 metals, such as indium-tin-oxide, may beused. Some non-limiting, specific examples of materials for anode layer(a) include indium-tin-oxide (“ITO”), aluminum-tin-oxide, gold, silver,copper, nickel, and selenium.

The anode layer (a) may be formed by a chemical or physical vapordeposition process or spin-cast process, inject or gravure printingprocess. Chemical vapor deposition may be performed as a plasma-enhancedchemical vapor deposition (“PECVD”) or metal organic chemical vapordeposition (“MOCVD”).

Physical vapor deposition can include all forms of sputtering (e.g., ionbeam sputtering), e-beam evaporation, and resistance evaporation.

Specific forms of physical vapor deposition include rf magnetronsputtering or inductively-coupled plasma physical vapor deposition(“ICP-PVD”). These deposition techniques are well-known within thesemiconductor fabrication arts.

A hole-transport layer (b) may be adjacent to the anode; this layer maybe split into a hole injecting (b1) and a hole transporting (b2) layer.Hole transporting small molecule compounds as well as polymers can beused.

Commonly used hole transporting molecules include:N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine(TPD), 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (TAPC),N,N′-bis(4-methylphenyl)-N,N′-bis(4-ethylphenyl)-[1,1′-(3,3′-dimethyl)biphenyl]4,4′-diamine(ETPD), tetrakis-(3-methylphenyl)-N,N,N′,N′-2,5-phenylenediamine (PDA),a-phenyl-4-N,N-diphenylaminostyrene (TPS),p-(diethylamino)benzaldehydediphenylhydrazone (DEH), triphenylamine(TPA), bis[4-(N,N-diethylamino)-2-methylphenyl](4-methylphenyl)methane(MPMP),1-phenyl-3-[p-(diethylamino)styryl]-5-[p-(diethylamino)phenyl]pyrazoline(PPR or DEASP), 1,2-trans-bis (9H-carbazol-9-yl)cyclobutane (DCZB),N,N,N′,N′-tetrakis(4-methylphenyl)-(1,1′-biphenyl)-4,4′-diamine (TTB),4,4′-N,N-dicarbazole-biphenyl (CBP),N,N-dicarbazoyl-1,4-dimethene-benzene (DCB),N,N′-Di(naphthalen-1-yl)-N,N′-diphenyl-benzidine (NPD),1,3-bis(9-carbazolyl)benzene (mCP), porphyrinic compounds,phthalocyanines, and combinations thereof. Further materials and methodsof use in this regard may be as described in US-A-2007-0087219 (seesections [0096]-[0154] therein), which passages are hereby incorporatedby reference.

Commonly used hole transporting polymers are polyvinylcarbazole,(phenylmethyl) polysilane, poly(3,4-ethylendioxythiophene) (PEDOT),triarylamine polymers (such aspoly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl))diphenylamine)][TFB]), polypyrrole, and polyaniline. Hole-transporting polymers can beobtained by doping hole-transporting molecules such as those mentionedabove into polymers such as polystyrene and polycarbonate.

The hole-injection/transport layer (b) can be formed using anyconventional means, including spin-coating, casting, and printing, suchas gravure printing. The layer can also be applied by ink jet printing,thermal patterning, or chemical or physical vapor deposition.

Usually, the anode layer (a) and the hole-injection/transport layer (b),if present, are patterned during the same lithographic operation. Thepattern may vary as desired. The layers can be formed in a pattern by,for example, positioning a patterned mask or resist on the firstflexible composite barrier structure prior to applying the firstelectrical contact layer material. Alternatively, the layers can beapplied as an overall layer (also called blanket deposit) andsubsequently patterned using, for example, a patterned resist layer andwet-chemical or dry-etching techniques. Other processes for patterningthat are well known in the art can also be used. When the electronicdevices are located within an array, the anode layer (a) and holeinjection/transport layer (b) typically are formed into substantiallyparallel strips having lengths that extend in substantially the samedirection. Layer (b) can be crosslinked.

The active layer (c) comprises the luminescent dopant and the polymer ofthe present invention. The particular material chosen may depend on thespecific application, potentials used during operation, or otherfactors. The active layer (c) may comprise a further host materialcapable of transporting electrons and/or holes, doped with an emissivematerial that may trap electrons, holes, and/or excitons, such thatexcitons relax from the emissive material via a photoemissive mechanism.Active layer (c) may comprise a single material that combines transportand emissive properties. Whether the emissive material is a dopant or amajor constituent, the active layer may comprise other materials, suchas dopants that tune the emission of the emissive material. Active layer(c) may include a plurality of emissive materials capable of, incombination, emitting a desired spectrum of light. Examples of emissivematerials include the phosphorescent metal compounds disclosed inWO06000544, WO06067074, WO07074093, and publications cited therein; aswell as certain fluorescent polyaryls as disclosed e.g. in EP-A-1138746,EP-A-1245659. Examples of fluorescent emissive materials include DCM andDMQA. Examples of further host materials include Alq₃, CBP and mCP.Examples of emissive and host materials are disclosed in U.S. Pat. No.6,303,238 B, which is incorporated by reference in its entirety.

Examples of methods for forming the active layer (c) include depositionby solution processing. Examples of film-forming methods from a solutioninclude application methods, such as spin-coating, casting, microgravurecoating, roll-coating, wire bar-coating, dip-coating, spray-coating,screen-printing, flexography, offset-printing, gravure printing andink-jet-printing.

As the composition used for forming the active layer (c) at least onekind of present polymers, a light emitting compound and at least onesolvent are contained, and additives, such as hole transport material,electron transport material, luminescent material, rheology modifier orstabilizer, may be added. The amount of solvent in the composition is 1to 99 wt % of the total weight of the composition and preferably 60 to99 wt % and more preferably 80 to 99 wt %.

The solvent used in the solution processing method is not particularlylimited and preferable are those which can dissolve or uniformlydisperse the materials. Preferably the materials may be dissolved in asolvent, the solution deposited onto a substrate, and the solventremoved to leave a solid film. Any suitable solvents may be used todissolve the compounds, provided it is inert, may dissolve at least somematerial and may be removed from the substrate by conventional dryingmeans (e.g. application of heat, reduced pressure, airflow, etc.).Suitable organic solvents include, but are not limited to, are aromaticor aliphatic hydrocarbons, halogenated such as chlorinated hydrocarbons,esters, ethers, ketones, amide, such as chloroform, dichloroethane,tetrahydrofuran, toluene, xylene, ethyl acetate, butyl acetate, methylethyl ketone, acetone, dimethyl formamide, dichlorobenzene,chlorobenzene, propylene glycol monomethyl ether acetate (PGMEA), andalcohols, and mixtures thereof. Also water and mixtures with watermiscible solvents are possible. Layer (c) can be crosslinked.

Optional layer (d) can function both to facilitate electroninjection/transport, hole blocking, and also serve as a buffer layer orconfinement layer to prevent quenching reactions at layer interfaces.More specifically, layer (d) may promote electron mobility and reducethe likelihood of a quenching reaction if layers (c) and (e) wouldotherwise be in direct contact. Examples of materials for optional layer(d) include metal-chelated oxinoid compounds (e.g.,tris(8-hydroxyquinolato)aluminum (Alq₃) or the like);phenanthroline-based compounds (e.g.,2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (“DDPA”),4,7-diphenyl-1,10-phenanthroline (“DPA”), or the like; azole compounds(e.g., 2-(4-biphenylyl)-5-(4-t-butylphenyl)-1,3,4-oxadiazole (“PBD”) orthe like, 3-(4-biphenylyl)-4-phenyl-5-(4-t-butylphenyl)-1,2,4-triazole(“TAZ”) or the like; other similar compounds; or any one or morecombinations thereof. Further materials and methods of use in thisregard may be as described in US-A-2006-0210830 (see sections[0076]-[0079] therein), and in US-A-2007-0042220 (see sections[0110]-[0114] therein), which passages are hereby incorporated byreference. Alternatively, optional layer (d) may be inorganic andcomprise BaO, LiF, Li₂O, or the like. Layer (d) can be crosslinked.

The electron injection/transport layer (d) can be formed using anyconventional means, including spin-coating, casting, and printing, suchas gravure printing. The layer can also be applied by ink jet printing,thermal patterning, or chemical or physical vapor deposition.

The cathode layer (e) is an electrode that is particularly efficient forinjecting electrons or negative charge carriers. The cathode layer (e)can be any metal or nonmetal having a lower work function than the firstelectrical contact layer (in this case, the anode layer (a)). Materialsfor the second electrical contact layer can be selected from alkalimetals of Group 1 (e.g., Li, Na, K, Rb, Cs), the Group 2 (alkalineearth) metals, the Group 12 metals, the rare earths, the lanthanides(e.g., Ce, Sm, Eu, or the like), and the actinides. Materials, such asaluminum, indium, calcium, barium, yttrium, and magnesium, andcombinations thereof, may also be used. Li-containing organometalliccompounds, LiF, and Li₂O can also be deposited between the organic layerand the cathode layer to lower the operating voltage. Specificnon-limiting examples of materials for the cathode layer (e) includebarium, lithium, cerium, cesium, europium, rubidium, yttrium, magnesium,or samarium.

The cathode layer (e) is usually formed by a chemical or physical vapordeposition process. In general, the cathode layer will be patterned, asdiscussed above in reference to the anode layer (a) and optional holeinjecting layer (b). If the device lies within an array, the cathodelayer (e) may be patterned into substantially parallel strips, where thelengths of the cathode layer strips extend in substantially the samedirection and substantially perpendicular to the lengths of the anodelayer strips.

Electronic elements called pixels are formed at the cross points (wherean anode layer strip intersects a cathode layer strip when the array isseen from a plan or top view).

In other embodiments, additional layer(s) may be present within organicelectronic devices. For example, a layer between the hole injectinglayer (b) and the active layer (c) may facilitate positive chargetransport, band-gap matching of the layers, function as a protectivelayer, or the like. Similarly, additional layers between the electroninjecting layer (d) and the cathode layer (e) may facilitate negativecharge transport, band-gap matching between the layers, function as aprotective layer, or the like. Layers that are known in the artgenerally may be used. Some or all of the layers may be surface treatedto increase charge carrier transport efficiency. The choice of materialsfor each of the component layers may be determined by balancing thegoals of providing a device with high device efficiency with the cost ofmanufacturing, manufacturing complexities, or potentially other factors.

The materials of the charge transport layers (b) and (d) often are ofthe same type as the materials of the active layer (c). Morespecifically, if the active layer (c) comprises a small moleculecompound, then the charge transport layers (b) and (d), if either orboth are present, often comprises a different small molecule compound.If the active layer (c) contains a polymer, the charge transport layers(b) and (d), if either or both are present, often contain a polymer,too. Still, the active layer (c) may contain a small molecule compound,and any of its adjacent layers (e.g. charge transport layers) may bepolymers.

Each functional layer may be made up of more than one layer. Forexample, the cathode layer may comprise a layer of a Group I metal and alayer of aluminum. The Group I metal may lie closer to the active layer(c), and the aluminum may help to protect the Group I metal fromenvironmental contaminants, such as water.

Although not meant to limit, the different layers may have the followingrange of thicknesses: inorganic anode layer (a), usually no greater thanapproximately 500 nm, for example, approximately 50-200 nm; optionalhole-injecting layer (b), usually no greater than approximately 100 nm,for example, approximately 50-200 nm; active layer (c), usually nogreater than approximately 100 nm, for example, approximately 10-80 nm;optional electron-injecting layer (d), usually no greater thanapproximately 100 nm, for example, approximately 10-80 nm; and cathodelayer (e), usually no greater than approximately 1000 nm, for example,approximately 30-500 nm. If the anode layer (a) or the cathode layer (e)needs to transmit at least some light, the thickness of such layer maynot exceed approximately 100 nm.

The location of the electron-hole recombination zone in the device, andthus the emission spectrum of the device, can be affected by therelative thickness of each layer. Thus, the thickness of theelectron-transport layer should be chosen so that the electron-holerecombination zone lies within the light-emitting layer (i.e., activelayer (c)). The desired ratio of layer thicknesses can depend on theexact nature of the materials used.

The efficiency of the devices made with metal complexes can be furtherimproved by optimizing the other layers in the device. For example, moreefficient cathodes such as Ca, Ba, Mg/Ag, or LiF/Al can be used. Shapedsubstrates and hole transport materials that result in a reduction inoperating voltage or increase quantum efficiency are also applicable.Additional layers can also be added to tailor the energy levels of thevarious layers and facilitate electroluminescence.

Depending upon the application of the electronic device, the activelayer (c) can be a light-emitting layer that is activated by a signal(such as in a light-emitting diode) or a layer of material that respondsto radiant energy and generates a signal with or without an appliedpotential (such as detectors or voltaic cells). Examples of electronicdevices that may respond to radiant energy are selected fromphotoconductive cells, photoresistors, photoswitches, phototransistors,and phototubes, and photovoltaic cells. Persons skilled in the art arecapable of selecting material(s) suitable for their particularapplication(s).

The electroluminescent devices may be employed for full color displaypanels in, for example, mobile phones, televisions and personal computerscreens. Accordingly the present invention relates also to a deviceselected from stationary and mobile displays, such as displays forcomputers, mobile phones, laptops, pdas, TV sets, displays in printers,kitchen equipment, billboards, lightings, information boards anddestination boards in trains and buses, containing an organic lightemitting diode according to the present invention.

In OLEDs, electrons and holes, injected from the cathode (e) and anode(a) layers, respectively, into the photoactive layer (c), form negativeand positively charged polarons in the active layer (c). These polaronsmigrate under the influence of the applied electric field, forming apolaron exciton with an oppositely charged species and subsequentlyundergoing radiative recombination. A sufficient potential differencebetween the anode and cathode, usually less than approximately 20 volts,and in some instances no greater than approximately 5 volts, may beapplied to the device. The actual potential difference may depend on theuse of the device in a larger electronic component. In many embodiments,the anode layer (a) is biased to a positive voltage and the cathodelayer (e) is at substantially ground potential or zero volts during theoperation of the electronic device. A battery or other power source (s)may be electrically connected to the electronic device as part of acircuit.

The compound does not need to be in a solid matrix diluent (e.g., hostcharge transport material) when used in layer (b) (c), or (d) in orderto be effective. A layer greater than approximately 1% by weight of themetal complex compound, based on the total weight of the layer, and upto substantially 100% of the present polymer can be used as the activelayer (c). Additional materials can be present in the active layer (c)with the complex compound. For example, a fluorescent dye may be presentto alter the color of emission.

A diluent may also be added. The diluent can be a polymeric material,such as poly(N-vinyl carbazole) and polysilane. It can also be a smallmolecule, such as 4,4′-N,N′-dicarbazole biphenyl or tertiary aromaticamines. When a diluent is used, the present polymer is generally presentin a small amount, usually less than 20% by weight, preferably less than10% by weight, based on the total weight of the layer.

The following test methods and examples are for illustrative purposesonly and are not to be construed to limit the instant invention in anymanner whatsoever. Room temperature (r.t.) depicts a temperature in therange 20-25° C.; over night denotes a time period in the range 12-16hours. Percentages are by weight unless otherwise indicated.

Abbreviations used in the examples or elsewhere:

-   AlBN azo-bis-isobutyronitrile-   CIE colour definition according to Commission Internationale de    l'Eclairage-   DMF dimethylformamide-   EE ethyl acetate-   EtOH ethanol-   HMPTA hexamethylphosphorus triamide-   Ir(ppy)₃ Iridium tris(2-phenylpyridine) (Baldo et al., Appl. Phys.    Lett. 1999, 75, 4-6)-   ITO indium tin oxide-   M_(w) molecular mass weight average-   M_(n) molecular mass number average-   PBD 2-(p-tert.butylphenyl)-5-biphenylyl-1,3,4-oxadiazole-   PDI polydispersity index (=ratio [M_(w)]/[M_(m)])-   PEDOT:PSS poly(3,4-ethylenedioxythiophene)poly(styrenesulfonate)-   PG polymerizable group-   QE quantum efficiency-   TBME tert.-butyl methyl ether-   THF tetrahydrofuran-   TPD N,N′-biphenyl-N,N′-di-m-tolyl-benzidine

Example 1

16.09 g (0.259 mol) of Potassium hydroxide (86%) are placed in a 500 mlthree necked round bottomed flask equipped with a magnetic stirrer and areflux condenser. 200 ml of THF and 6.5 ml of Dichloromethane are added.The mixture is refluxed. After 1 hour the mixture is cooled to roomtemperature. A solution of 8 g (37.74 mmol) dibenzofuran-4-boronic acid,0.8 g (3.02 mmol) of Triphenylphosphine, 339 mg (0.7 mmol) of Palladium(II) acetate and 200 ml of Methanol are added. The reaction mixture isheated to 60° C. internal temperature. After 2 hours the reaction iscomplete and cooled down to room temperature. The mixture is dilutedwith H₂O and Ethylacetate. The organic phase is extracted twice withwater and once with brine. The organic phase is dried over Sodiumsulfateand the solvent evaporated. The crude product is purified by columnchromatography (Heptane). 4-Vinyl-dibenzofuran is isolated in 42% yield.

¹H-NMR (300 MHz, CDCl₃):

-   -   7.94 (d,1H)    -   7.84 (d, 1H)    -   7.61 (d, 1H)    -   7.50 (m, 2H)    -   7.36 (m, 2H)    -   7.12 (dxd 1H)    -   6.32 (d, 1H)    -   5.60 (d, 1H)

Example 2

22.7 g (63.7 mmol) of Methyl triphenylphosphonium bromide and 200 ml ofdry THF are placed in a dried 500 ml three necked round bottomed flask,equipped with a magnetic stirrer and the reaction mixture is cooled to0° C. internal temperature with a NaCl/ice bath. 41.8 ml (66.9 mmol) of1.6 M Butyl lithium solution in Hexane are added within 30 minutes whilekeeping the internal temperature below 3° C. The reaction mixture isstirred at the same temperature for 45 minutes, then 47.2 mmol ofDibenzofuran-2-carboxaldehyde dissolved in 100 ml of dry THF are addedwithin 30 minutes. After two hours the reaction mixture is warmed toroom temperature, added to 500 ml of water and extracted three timeswith 500 ml of Ethylacetate. The combined organic phases are washed oncewith 500 ml of a 1:1 mixture of buffer pH=1 and brine, once with 30 mlof brine, dried over Magnesiumsulfate, filtered and evaporated. Thecrude product is dissolved in Dichloromethane, 100 g of silica are addedand the solvent is evaporated. The resulting powder is added on top of300 g of silica in a sintered glass funnel and the product eluted withHexane/Ethylacetate=8:1. The product is crystallized from 2-Propanol.2-Vinyl-dibenzofuran is isolated in 95% yield.

¹H-NMR (300 MHz, CDCl₃):

-   -   7.94 (d, 1H)    -   7.98-7.92 (m, 2H)    -   7.64-7.32 (m, 5H)    -   6.92 (dxd 1H)    -   5.82 (d, 1H)    -   5.30 (d, 1H)

Example 3

1 g 4-Vinyl-dibenzofuran (example 1) and 0.01 eq. of the initiatorindicated in the above scheme are dissolved in 0.5 ml chlorobenzene,degassed and stirred under nitrogen at 120° C. for 24 h. The product ispurified by multiple precipitation in MeOH. Yield 70%. GPC: Mn=13600,PDI=1.16.

Example 4

1.24 g 2-Vinyl-dibenzofurane (example 2) and 1.5 weight % of AlBN aredissolved in 5 ml toluene, degassed and polymerized under inertatmosphere for 24 h at 80° C. The polymer is purified by multipleprecipitation in methanol. Yield 83%. GPC: Mn=19800, PDI=1.96.

Example 5

16.8 g (90.1 mmol) of benzofurane, 19.7 g (80 mmol) iodine, 7.7 g (44mmol) Iodic acid are dissolved in 200 ml acidic acid, 15 ml water, 2 mlsulphuric acid and 10 ml carbon tetrachloride, and stirred at 65° C. for30 h. The product is filtered off, redissolved in hot toluene andprecipitated again by adding methanol. 2,8-Diiododibenzofurane (5.1) isisolated in 60.7% yield.

¹H-NMR (300 MHz, CDCl₃):

-   -   8.2 (s, 2H)    -   7.74 (d, 2H)    -   7.33 (d, 2H)

4 g (13.5 mmol) of 2,8-Diiododibenzofurane are dissolved in 100 ml ofdry THF. 17.8 ml of 1,6M n-Buthyllithium solution in hexane is addeddropwise at −78° C. After stirring for 1 h at −78° C., a solution of 8.8g (29.84 mmol) of chlorotriphenylsilane in 20 ml THF is added. Thereaction mixture is allowed to warm to RT and is quenched with saturatedammonium chloride solution. The organic phase is filtered and theproduct purified by recrystallization from THF, resulting in 5.62 g(60%) of 2,8-di-(triphenylsilyl)-dibenzofurane (5.2).

¹H-NMR (300 MHz, CDCl₃):

-   -   8.08 (s, 2H)    -   6.68-7.58 (m, 16H)    -   7.49-7.36 (m, 18H)

1 g (1.46 mmol) 2,8-di-(triphenylsilyl)-dibenzofuran are dissolved in100 ml dry THF at 45° C. and 10 ml of 1.4 M sec-Buthyllithium solutionin cyclohexane is added. After stirring for 15 min. at 45° C., 2 ml ofdry DMF is added; the reaction mixture is stirred for 1 h. 100 ml of 0.5M HCl is added to quench the reaction. The product is extracted withethylacetate and purified by column chromatography on silica gel withheptane:ethylacetate (3:1) as an eluent.2,8-di-(triphenylsilyl)-dibenzofuran-4-carboxaldehyde (5.3) is obtainedin 30.2% yield.

¹H-NMR (300 MHz, CDCl₃):

-   -   10.5 (s, 1H)    -   8.30 (s, 1H)    -   8.15 (s, 1H)    -   8.11 (s, 1H)    -   7.73-7.55 (m, 14H)    -   7.49-7.36 (m, 18H)

2,8-Di-(triphenylsilyl)-dibenzofuran-4-carboxaldehyde is reacted withMethyl triphenylphosphonium bromide according to the method of example 2to give 4-Vinyl-2.8-di-(triphenylsilyl)-dibenzofurane (5.4) in 37.8%yield.

¹H-NMR (300 MHz, CDCl₃):

-   -   7.99 (s, 1H)    -   7.88 (s, 1H)    -   7.57-7.48 (m, 15H)    -   7.40-7.26 (m, 18H)    -   6.93 (dd, 1H)    -   6.14 (d, 1H)    -   5.46 (d, 1H)

Polymer 3 is obtained according to the method of example 4 in 30% yield.GPC: Mn=6400, PDI=1.26.

Example 6

In analogy to the methods given in example 5 and according to thefollowing reaction scheme, polymers 4 and 5 are obtained:

Example 7

In analogy to the methods given in example 5 and according to thefollowing reaction scheme, polymer 6 is obtained:

Application Examples

An organic luminescence device having a single organic layer is preparedin the following manner: On a glass substrate, a 80 nm thick ITO film isformed by sputtering and subsequently patterned. Onto the oxygen-plasmatreated ITO film, a hole-injection layer of 80 nm thickness is formed byspin-coating using PEDOT:PSS (Baytron P), followed by heating at 200° C.(10 minutes). A solution of 15 mg of a polymer of the invention, 1.25 mgof TPD, 7.5 mg of PBD and 1.25 mg of Ir(ppy)₃ in 1.1 ml of toluene isapplied by spin coating (3100 rpm.; 40 seconds) to obtain a thickness of80 nm. The film is dried under nitrogen atmosphere at 80° C. for 30minutes. The substrate is placed in a vacuum deposition chamber, and acathode having a two-layer structure is formed by depositing a 5 nmlayer of barium followed by a 70 nm layer of aluminum. Details ofoperating and device efficiency are compiled in the following table.

Max. QE cd/A @ V @ Compound in % 1000 cd/qm 1000 cd/qm CIE x CIE yPolymer 1 8.8 12.0 0.3 0.63 Polymer 2 3.07 9.8 12.3 0..3 0.63

The invention claimed is:
 1. Electroluminescent composition comprising ahomopolymer of formula III

wherein n ranges from 2 to 10000; L is CH₂, CO or a direct bond; R⁹,R¹¹, R¹³, R¹⁴, are selected from H, C₁-C₁₈alkyl, halogen, C₁-C₁₈alkylwhich is substituted by E and/or interrupted by D, C₆-C₂₄aryl,C₆-C₂₄aryl which is substituted by G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl,C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which is substituted by E and/or interruptedby D, C₇-C₂₅aralkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂, or is —CO—R²⁸; eachof the residues R^(9″) is independently selected from those defined forR⁹, Rx is H or methyl, SP is a divalent organic spacer, X10 is o or 1; Dis —CO—; —COO—; —S—; —SO—; —SO₂—; —O—; —NR²⁵—; —SiR³⁰R³¹—; —POR³²—;—CR²³═CR²⁴—; or —C≡C—; and E is —OR²⁹; —SR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷;—CONR²⁵R²⁶; —CN; or halogen; G is E, C₁-C₁₈alkyl, C₃-C₁₂cycloalkyl,C₂-C₁₈alkyl which is interrupted by D, C₁-C₁₈perfluoroalkyl, orC₁-C₁₈alkoxy which is substituted by E and/or interrupted by D, whereinR²³, R²⁴, R²⁵ and R²⁶ are independently of each other H; C₆-C₁₈aryl;C₆-C₁₈arylalkyl; C₃-C₁₂cycloalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkyl whichis substituted by C₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl; orC₂-C₈alkyl which is interrupted by —O—; or R²⁵ and R²⁶ together form afive or six membered ring; R²⁷ and R²⁸ are independently of each otherH; C₆-C₁₈aryl; C₆-C₁₈arylalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkyl which issubstituted by C₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl;C₃-C₁₂cycloalkyl; or C₂-C₁₈alkyl which is interrupted by —O—; R²⁹ is H;C₆-C₁₈aryl; C₆-C₁₈arylalkyl; C₆-C₁₈aryl or C₆-C₁₈arylalkyl which issubstituted by C₁-C₁₈alkyl and/or C₁-C₁₈alkoxy; C₁-C₁₈alkyl;C₂-C₁₈alkylcarbonyl; C₃-C₁₂cycloalkyl; or C₂-C₁₈alkyl orC₂-C₈alkylcarbonyl which is interrupted by —O—; R³⁰ and R³¹ areindependently of each other C₁-C₁₈alkyl, C₃-C₁₂cycloalkyl, C₆-C₁₈aryl,or C₆-C₁₈aryl, which is substituted by C₁-C₁₈alkyl, and R³² isC₁-C₁₈alkyl, C₆-C₁₈aryl, or C₆-C₁₈aryl, which is substituted byC₁-C₁₈alkyl, R, R′ and R″ independently are selected from C₁-C₁₂alkyl,C₁-C₁₂haloalkyl, C₅-C₁₀aryl, C₃-C₁₂cycloalkyl; and Ar independently isselected from C₅-C₁₀aryl, or C₅-C₁₀aryl which is substituted byC₁-C₁₈alkyl; and a luminescent component selected from phosphorescentmetal complexes and fluorescent dopants.
 2. Electroluminescentcomposition of claim 1, wherein n ranges from 5 to 5000; X10 is 0; R⁹,R^(9″), R¹¹, R¹³, R¹⁴, are selected from H, C₁-C₈alkyl, fluoro,C₁-C₈alkyl which is substituted by E, C₂-C₁₈alkyl which is interruptedby D, phenyl, phenyl which is substituted by G, C₂-C₈alkenyl,C₂-C₈alkynyl, C₁-C₈alkoxy, C₁-C₈alkoxy which is substituted by E,C₂-C₁₈alkoxy which is interrupted by D, C₇-C₂₅phenylalkyl, SiRR′R″,GeRR′R″, POAr₂, PAr₂, or is —CO—R²⁸; D is —CO—; —COO—; —S—; —SO—; —SO₂—;—O—; —NR²⁵—; —SiR³OR³¹—; —POR³²—; and E is —OR²⁹; —NR²⁵R²⁶; —COR²⁸;—COOR²⁷; —CONR²⁵R²⁶; —CN; or halogen; G is E, C₁-C₈alkyl, cyclohexyl,C₂-C₁₈alkyl which is interrupted by D, C₁-C₈ perfluoroalkyl,C₁-C₁₈alkoxy which is substituted by E, C₂-C₁₈alkoxy which isinterrupted by D, wherein R²⁵ and R²⁶ are independently of each other H;phenyl; C₇-C₁₂phenylalkyl; cyclohexyl; phenyl or C₇-C₁₂phenylalkyl whichis substituted by C₁-C₈alkyl or C₁-C₈alkoxy; C₁-C₁₈alkyl; or C₂-C₁₈alkylwhich is interrupted by —O—; or R²⁵ and R²⁶ together form a five or sixmembered ring selected from

R²⁷ and R²⁸ are independently of each other H; phenyl;C₇-C₁₂phenylalkyl; phenyl or C₇-C₁₂phenylalkyl which is substituted byC₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl; cyclohexyl; or C₂-C₁₈alkylwhich is interrupted by —O—; R²⁹ is H; phenyl; C₇-C₁₂phenylalkyl; phenylor C₇-C₁₂phenylalkyl which is substituted by C₁-C₈alkyl and/orC₁-C₈alkoxy; C₁-C₈alkyl; C₂-C₈alkylcarbonyl; cyclohexyl; or C₂-C₁₈alkylor C₂-C₁₈alkylcarbonyl which is interrupted by —O—; R³⁰ and R³¹ areindependently of each other C₁-C₈alkyl, phenyl, or phenyl which issubstituted by C₁-C₈alkyl, and R³² is C₁-C₈alkyl, phenyl, or phenylwhich is substituted by C₁-C₈alkyl, R, R′ and R″ independently areselected from C₁-C₆alkyl, phenyl, cyclopentyl, cyclohexyl; and Ar isphenyl or phenyl substituted by C₁-C₈alkyl.
 3. Electroluminescentcomposition according to claim 1 containing 10 to 1000 structural unitsof the formula, wherein X10 is 0; any of R⁹, R^(9″), R¹¹, R¹³, R¹⁴,independently is selected from H, C₁-C₈alkyl, fluoro, C₁-C₈alkyl whichis substituted by E, C₂-C₁₈alkyl which is interrupted by D, phenyl,phenyl which is substituted by G, C₂-C₈alkenyl, C₂-C₈alkynyl,C₁-C₈alkoxy, C₁-C₈alkoxy which is substituted by E, C₂-C₁₈alkoxy whichis interrupted by D, C₇-C₂₅phenylalkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂,or is —CO—R²⁸; D is —CO—; —COO—; —O—; —NR²⁵—; —SiR³OR³¹—; and E is−OR²⁹; —NR²⁵R²⁶; —COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; or fluoro; G is E orC₁-C₈alkyl; R²⁵ and R²⁶ are independently of each other H; C₁-C₈alkyl;cyclohexyl; R²⁷ and R²⁸ are independently of each other H; phenyl;benzyl; phenyl or benzyl which is substituted by C₁-C₈alkyl and/orC₁-C₈alkoxy; C₁-C₈alkyl; R²⁹ is H; phenyl; benzyl; phenyl or benzylwhich is substituted by C₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl;acetyl; cyclohexyl; or C₂-C₁₂alkyl which is interrupted by —O—; R³⁰ andR³¹ are independently of each other methyl or phenyl, and R, R′ and R″independently are selected from methyl, ethyl, phenyl; and Ar is phenyl.4. Electroluminescent composition of claim 1, wherein any of R⁹, R^(9″),R¹¹, R¹³, R¹⁴, independently is selected from H, C₁-C₈alkyl, SiRR′R″. 5.Electroluminescent composition as defined in claim 1, which comprisesone or more further component(s)selected from electron transporters,hole transporters, inert polymers, viscosity modifiers, initiators,organic salts, and stabilizers.
 6. An organic electronic device,comprising a layer of an electroluminescent material according toclaim
 1. 7. A device according to claim 6 selected from stationary andmobile displays.
 8. Homopolymer of the formula III′

wherein n ranges from 5 to 10000; at least one of the residues R⁹,R^(9″), R¹¹, R¹³, R¹⁴ is selected from C₁-C₁₈alkyl, halogen, C₁-C₁₈alkylwhich is substituted by E and/or interrupted by D, C₆-C₂₄aryl,C₆-C₂₄aryl which is substituted by G, C₂-C₁₈alkenyl, C₂-C₁₈alkynyl,C₁-C₁₈alkoxy, C₁-C₁₈alkoxy which is substituted by E and/or interruptedby D, C₇-C₂₅aralkyl, SiRR′R″, GeRR′R″, POAr₂, PAr₂, CO—R²⁸; while theremaining residues may also be hydrogen; D is —CO—; —COO—; —S—; —SO—;—SO₂—; —O—; —NR²⁵—; —SiR³OR³¹—; —POR³²—; and E is —OR²⁹; —NR²⁵R²⁶;—COR²⁸; —COOR²⁷; —CONR²⁵R²⁶; —CN; or halogen; G is E, C₁-C₈alkyl,cyclohexyl, C₂-C₁₈alkyl which is interrupted by D, C₁-C₈ perfluoroalkyl,C₂-C₁₈alkoxy which is substituted by E, C₂-C₁₈alkoxy which isinterrupted by D, wherein R²⁵ and R²⁶ are independently of each other H;phenyl; C₇-C₁₂phenylalkyl; cyclohexyl; phenyl or C₇-C₁₂phenylalkyl whichis substituted by C₁-C₈alkyl or C₁-C₈alkoxy; C₁-C₁₈alkyl; or C₂-C₁₈alkylwhich is interrupted by —O—; or R²⁵ and R²⁶ together form a five or sixmembered ring selected from

R²⁷ and R²⁸ are independently of each other H; phenyl;C₇-C₁₂phenylalkyl; phenyl or C₇-C₁₂phenylalkyl which is substituted byC₁-C₈alkyl and/or C₁-C₈alkoxy; C₁-C₈alkyl; cyclohexyl; or C₂-C₁₈alkylwhich is interrupted by —O—; R²⁹ is H; phenyl; C₇-C₁₂phenylalkyl; phenylor C₇-C₁₂phenylalkyl which is substituted by C₁-C₈alkyl and/orC₁-C₈alkoxy; C₁-C₈alkyl; C₂-C₈alkylcarbonyl; cyclohexyl; or C₂-C₁₈alkylor C₂-C₁₈alkylcarbonyl which is interrupted by —O—; R³⁹ and R³¹ areindependently of each other C₁-C₈alkyl, phenyl, or phenyl which issubstituted by C₁-C₈alkyl, and R³² is C₁-C₈alkyl, phenyl, or phenylwhich is substituted by C₁-C₈alkyl, R, R′ and R″ independently areselected from C₁-C₆alkyl, phenyl, cyclopentyl, cyclohexyl; and Ar isphenyl or phenyl substituted by C₁-C₈alkyl; L is CH₂, CO or a directbond; Rx is H or methyl; X10 is 0 or 1 and Sp is O, C₁-C₄alkylene-O,CH₂—CHOH—CH₂—O, COO, CONR22, C₁-C₄alkylene, or CH₂CHOHCH₂.
 9. Compoundof the formula V

wherein at least one of the residues R⁹, R^(9″), R¹¹, R¹³, R¹⁴ isselected from halogen, C₂-C₁₈alkynyl, C₁-C₁₈alkoxy, SiRR′R″, GeRR′R″,POAr₂, PAr₂; R, R′ and R″ independently are selected from C₁-C₆alkyl,phenyl, cyclopentyl, cyclohexyl; and Ar is phenyl or phenyl substitutedby C₁-C₈alkyl; L is CH₂, CO or a direct bond; Rx is H or methyl; X10 is0 or 1 and Sp is O, C₁-C₄alkylene-O, CH₂—CHOH—CH₂—O, COO, CONR22,C₁-C₄alkylene, or CH₂CHOHCH₂.